Hydro Turbine

ABSTRACT

A hydro turbine includes at least two annular wheel discs, a center shaft disposed at the centers of the annular wheel discs, spokes disposed between the annular wheel discs and the center shaft, and a plurality of blades annularly disposed at the annular wheel discs. The number of the blades is at least 28 and at most the integer number of an outer circumference measured in centimeters of one annular wheel disc. The sum of arc length of one side of all the blades is 0.85-2 times the outer circumference. A blade angle formed between two line segments connecting the middle point to the two endpoints of an arc of each blade is in a range of 100°-170°. A blade installation angle formed between the chord line of the arc and a radius line of each annular wheel disc is in a range of 15°-75°.

CROSS-REFERENCE TO RELATED APPLICATIONS

This Non-provisional application claims priority of Chinese PatentApplication No. 201310074235.0 filed on Mar. 8, 2013, the entirecontents of which are hereby incorporated by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a hydro turbine.

2. Description of the Related Art

Tidal hydro turbines in the prior art mainly use wind power generationtechnology for reference and are classified into two kinds. One kind isthe hydro turbine with a horizontal shaft. The impeller of the hydroturbine has only two or three blades, usually without a large flowguiding dome, but the efficiency thereof is generally low. The otherkind is the hydro turbine with a vertical shaft borrowing ideas from thewind power generation. The impeller of the hydro turbine basically hasthree to five blades, and some have more than ten blades. This impelleris a traditional double-impact impeller and has efficiency slightlyhigher than that of the impeller of the three-blade hydro turbine withthe horizontal shaft, on condition that a large flow guiding dome isprovided.

Nowadays, with the increasing shortage of energy and the increasingserious greenhouse effect, energy is required to be low-carbon. Thus,clean energy, such as wind energy and ocean energy (including tidalenergy, the tidal current energy, the ocean wave energy, and the oceancurrent energy), will be the future direction of energy development.However, the power generating devices for the clean energy are stilldeveloping, and the utilization of ocean energy is still in the initialstage, except for the relatively mature wind energy utilization. Nocommon and mature devices are available. The devices cannot belarge-scaled, have low efficiency, and fail to reach a completelysatisfied level.

SUMMARY

To overcome the technical deficiencies in the prior art, the presentinvention provides a hydro turbine having multiple blades and highefficiency.

To fulfill the mentioned aim, the present invention adopts the followingtechnical solutions. A hydro turbine includes at least two annular wheeldiscs, a center shaft, a plurality of spokes, and a plurality of blades.The center shaft is disposed at the centers of the annular wheel discs.The axis direction of the center shaft is vertical to radial directionsof the annular wheel discs. The spokes are disposed between the annularwheel discs and the center shaft and disposed along the radialdirections of the annular wheel discs. A plurality of blades isannularly disposed at the annular wheel discs. The number of the bladesis at least 28 and at most the integer number of an outer circumferencemeasured in centimeters of one annular wheel disc. The blades arearc-shaped, and the sum of arc length of one side of all the blades is0.85-2 times the outer circumference of one annular wheel disc. A bladeangle is formed between two line segments respectively connecting themiddle point to the two endpoints of an arc of each blade, and the bladeangle is in a range of 100°-170°. A blade installation angle is formedbetween the chord line having the maximum chord length of the arc ofeach blade and a radius line of each annular wheel disc passing throughan outer endpoint of the blade, and the blade installation angle is in arange of 15°-75°.

Preferably, the center shaft is a hollow shaft.

Preferably, the hydro turbine further includes two cover platesrespectively disposed on sides of the two annular wheel discs back tothe blades.

The present invention has the following beneficial effects: theefficiency of the hydro turbine is directly proportional to the numberof the blades, so the increase of the number of the blades can greatlyimprove the working efficiency. Experimental data shows that theefficiency of the power generation device using the hydro turbine in theinvention is 1.4-1.5 times that of the traditional vertical-shaft powergeneration device. In addition, the friction force between the hydroturbine and the center shaft is reduced by the buoyancy of the hollowcenter shaft generated by itself, so the working efficiency iseffectively improved. Further, the hydro turbine is applicable to tidalcurrent and has self-startup capabilities at various current speeds.

These and other features, aspects, and advantages of the presentinvention will become better understood with regard to the followingdescription, appended claims, and accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a front view showing a hydro turbine of the present invention;

FIG. 2 is a top view showing the hydro turbine of the present invention;

FIG. 3 is a structural view of the blade angle of the present invention;and

FIG. 4 is a structural view of the blade installation angle of thepresent invention.

DETAILED DESCRIPTION

To ensure that those skilled in the art better understand the scheme ofthe present invention, the technical scheme in the embodiment is clearlyand completely described below with reference to drawings attached tothe embodiment of the present invention. Obviously, the embodiment isonly a schematic one of the present invention and cannot be regarded aslimit of the present invention. Based on the embodiment in the presentinvention, all other embodiments made by those skilled in the artwithout creative labor all belong to the protection scope of the presentinvention.

The following embodiment of the present invention is described withreference to the attached drawings. A hydro turbine includes a centershaft 1 and at least two annular wheel discs 2. The center shaft 1 isinstalled at the centers of the annular wheel discs 2. The axisdirection of the center shaft 1 is vertical to radial directions of theannular wheel discs 2. Spokes 3 are installed between the annular wheeldiscs 2 and the center shaft 1 and disposed along the radial directionsof the annular wheel discs 2. A plurality of blades 4 is fixedlyinstalled at the annular wheel discs 2. The length directions of theblades 4 are parallel to the center shaft 1. If the blades 4 of thehydro turbine are relatively long, a plurality of annular wheel discs 2can be uniformly installed along the axis direction of the center shaft1 according to actual requirements, and a plurality of blades 4 isannularly disposed among the annular wheel discs 2. That is, the longerblades are cut into shorter ones and connected into a whole through themultiple annular wheel discs 2, so as to improve firmness. The number ofthe blades 4 is at least 28 and at most the integer number of an outercircumference measured in centimeters of one annular wheel disc 2. Forexample, the outer circumference of the annular wheel disc 2 is 98.3 or98.8 cm, and then the number of the blades 4 can be 98. The blades 4 arearc-shaped. The sum of arc length of one side of all the blades 4 is0.85-2 times the outer circumference of one annular wheel disc 2. Thementioned side of all the blades is shown in FIG. 2. That is, the arclength of all the arcs of the blades shown in FIG. 2 is 0.85-2 times theouter circumference of the annular wheel disc 2. A blade angle A isformed between two line segments respectively connecting the middlepoint to the two endpoints of an arc of each blade 4 (as shown in FIG.3), and the blade angle A is larger than or equal to 100 degrees and issmaller than or equal to 170 degrees. A blade installation angle B isformed between the chord line having the maximum chord length of the arcof each blade 4 and a radius line of each annular wheel disc 2 passingthrough an outer endpoint of the blade 4 (as shown in FIG. 4), and theblade installation angle B is larger than or equal to 15 degrees and issmaller than or equal to 75 degrees. In actual use, the bladeinstallation angle may be 15°, 45°, 60°, etc.

In certain cases, the efficiency of the hydro turbine is directlyproportional to the number of the blades 4, thereby greatly improvingthe efficiency. Experimental data shows that the efficiency of the powergeneration device using the hydro turbine in the invention is 1.4-1.5times that of the traditional vertical-shaft power generation device. Inaddition, the center shaft 1 is a hollow shaft, and the friction forcebetween the hydro turbine and the center shaft 1 is reduced by thebuoyancy of the hollow center shaft 1 generated by itself, so theworking efficiency is effectively improved. Moreover, the hydro turbineis applicable to tidal current and has self-startup capabilities atvarious current speeds.

In the embodiment, the hydro turbine further includes two cover plates 5respectively disposed on sides of the two annular wheel discs 2 back tothe blades 4. As shown in FIG. 1, the cover plates 5 are respectivelylocated above the upper annular wheel disc 2 and below the lower annularwheel disc 2. Via the cover plates 5, water can be effectively preventedfrom entering from the gaps between the center shaft 1 and the annularwheel discs 2 from the upside and the lower side, thereby ensuring theworking efficiency of the hydro turbine.

What is claimed is:
 1. A hydro turbine, comprising: at least two annularwheel discs; a center shaft, disposed at the centers of the annularwheel discs, the axis direction of the center shaft being vertical toradial directions of the annular wheel discs; a plurality of spokes,disposed between the annular wheel discs and the center shaft anddisposed along the radial directions of the annular wheel discs; and aplurality of blades, annularly disposed at the annular wheel discs,wherein the number of the blades is at least 28 and at most the integernumber of an outer circumference measured in centimeters of one annularwheel disc, the blades are arc-shaped, the sum of arc length of one sideof all the blades is 0.85-2 times the outer circumference of one annularwheel disc, a blade angle is formed between two line segmentsrespectively connecting the middle point to the two endpoints of an arcof each blade, the blade angle is in a range of 100°-170°, a bladeinstallation angle is formed between the chord line having the maximumchord length of the arc of each blade and a radius line of each annularwheel disc passing through an outer endpoint of the blade, and the bladeinstallation angle is in a range of 15°-75°.
 2. The hydro turbineaccording to claim 1, wherein the center shaft is a hollow shaft.
 3. Thehydro turbine according to claim 1, further comprising two cover platesrespectively disposed on sides of the two annular wheel discs back tothe blades.